Project Summary Filoviruses, including the Ebola viruses, Marburg viruses, and Cueva virus, are a class of pathogens with enormous health implications. Filoviruses have been implicated in numerous outbreaks in Africa, including the ongoing outbreak in the Democratic Republic of Congo (DRC), potential risk as an agent of bioterrorism, and the potential risk of transmission to non-endemic countries such as the United States. Critical in both the management of outbreaks as well as the treatment of infected patients are specific and rapid diagnostic tests. Despite the critical health risk posed by these pathogens, current diagnostic techniques utilizing PCR and ELISAs have significant limitations, including the need for centralized laboratories, cold-chain custody, and limited diagnostic ability in the early stages of infection. This proposal seeks to fill this gap and leverage a highly sensitive class of optical sensors, whispering gallery mode (WGM) devices, for the rapid detection of filovirus glycoproteins (GP) and the ebolavirus soluble glycoprotein (sGP), two highly sensitive biomarkers for filoviruses. WGM sensors are a unique class of optical devices in which light is confined to a small volume, therefore leading to an enormous enhancement in signal response. In addition to their sensitivity, these devices also offer the advantages of inexpensive and scalable fabrication costs, the ability to be integrated with conventional electronics, and the potential for multiplexed measurements. In combination with these devices will be antibodies against filovirus GP and sGP, the latter an enormously powerful sentinel biomarker that is positive hours to days before presentation of symptoms in infected individuals. This academic-industry partnership will develop a rapid and sensitive diagnostic test for filovirus GP and sGP, and subsequently lay the foundation for the developing this technology into a powerful, field-deployable device for filovirus detection.